1961-022
The second in the series, S-055A, reached orbit on 1961 Aug 25. Ascent was at an 80 degree elevation and 90 deg (eastward) azimuth. However, the orbit was lower than planned, 125 x 1164 km x 37.7 deg, due to a large injection angle error. (TN-D-1396 indicates initial perigee was 139 km, with an injection angle of -4.396 degrees; injection altitude was 455.6 km, so injection velocity was around 7.748 km/s).
The S-55 satellite was attached to the Altair X-248-A5 stage and a set of pressurized cells was installed around the rocket stage. Mass was 57 kg payload; 86 kg including the 22 kg empty Altair and upper 'D' Scout section, which was 6 kg. Size was 1.93m long 0.58m dia. LaRC managed the project, with detectors from LaRC, LeRC and GSFC.
| Explorer 13 | |||
| Date | Time | Event | Orbit |
|---|---|---|---|
| 1961 Aug 25 | 1829:44 | Launch by Scout ST-6 | WI |
| T+0:42 St 1 Algol burnout 1.1 km/s 15 km | |||
| T+1:14 St 1 sep | |||
| T+1:14 St 2 Castor burn 38 km 0.9 km/s | |||
| 1831:41 | T+1:57 St 2 burnout 76 km 2.7 km/s | ||
| T+1:57 St 3 heat shield sep | |||
| 1831:59 | T+2:15 Fairing sep 107 km | ||
| 1831:59 | St 2 sep | ||
| 1831:59 | T+2:15 St 3 Antares burn, 107 km 2.7 km/s | ||
| 1832:36 | T+2:52 St 3 burnout | ||
| Coast | |||
| 1837:46 | Spinup to 190 rpm | ||
| 1837:48 | T+8:04 St 3 sep | ||
| 1837:48 | T+8:04 St 4 Altair burn 453 km | ||
| 1838:29 | T+8:45 St 4 burnout | ||
1961 Aug 25 | (Minitrack) | 113 x 1147 x 37.7 | |
| 1961 Aug 26 | 97.5 125 x 1164 x 37.7 | ||
| 1961 Aug 28 | Reentered | ||
Payload:
- X-248A5 motor
- Langley pressurized cell detector (five rows of 32 cells each, outside X-248)
- LeRC Grid detector (60), aft section
- GSFC Cu wire card detector (46), aft section
- LaRC Impact detector (2), nose section
- Solar cell experiments, nose section